Blow-out preventer



I Nov.` 5,I 1935.

M. S. BLACK BLOW-OUT PREVENTER Filed June 10, 1955 l Patented Nov. 5, 1935 UNITED STATES PATENT OFFICE 2,019,885 Bmw-our PnEvnN'mn Millard s. Black, Huntington Park, onuf. Application June 1o, 1933. sel-inl Nn. 615,283

17 Claims.

This invention is a blow-out preventer having expansible packing disposed between a well casing and a string of well `tubing or the like; and it is an object of the invention to provide a construction whereby only a relatively small force need be exerted for operatively expanding the packing so as to exert a relatively heavy pressure against both the .casing and tubing for insuring a tight pack-o.

It is a further object of the 4invention to adapt the blow-out preventer for convenient operative placement or removal, and to provide a simplified but practical means for releasably lockingv the blow-out preventer in operative position.

More particularly it is an object of the invention to provide a structure including an outer packing-shell adapted for mounting lin a well casing and an inner bushing adapted for mounting in the shell and surrounding the well tubing, with the outer shell comprising upper and lower retaining rings rigid with relation to one another and having interposed packing of relatively large area for radial engagement with the bore of the well casing, and the inner bushing comprising upper and lower glands longitudinally movable relative to one another and having interposed packing radially engaging. the tubing and the packing ofthe outer shell, with the inner bushing of relatively small vcross-sectional area so that a relatively small force exerted on the bushing for longitudinally compressing and thereby radially expanding its packing, is transmitted to the packing element of the outer shell for radially expanding the latterso that its relatively large engaging area exerts a relatively heavy pressure against the'well casing.

It is a further object of the invention to form the shell and bushingas split structures adapted for relative displacement or assembly of their complemental parts for convenient removal or operative mounting of the blow-out preventer, with the upper and lower glands ofn the bushing relatively longitudinally movable but held against vdisplacement from the shell, and the shell retained in the well casing by a readily releasabl locking means which is positioned entirely within the bore of the casing so that the outer periphery of the casing lis clear of obstructions and thus adapted for reception of a bonnet or an upwardly extending additional string of casing when such an assembly is desired.

The packing of the blow-out preventer is readily adjustable so that it is applicable to well tubing'which varies in size, thereby providing a com- .mercially practical device'adapted to meet the varying conditions encountered in actual use.

Further object of the invention will be readily understood from the following description of the accompanying drawing, in which:

Fig. 1 is a. Vfront elevation of the blow-out preventer in operative position, and shown partly in axial section.

Fig. 2 is a transverse section on the line 2 2 of Fig. 1. 5 Fig. 3 is a longitudinal section on the line 3 3 of Fig. 2.

Fig. 4 is a fragmentary axial section showing the method of releasing and removing the blowout preventer.

The blow-out preventer is adapted to pack-oil the annular space between a string of tubing or the like shown at I anda surrounding well casing 2; and is preferably mounted in a cylindrical head 3 which is fixed to the upper end of the 15 casing and which may be provided with usual lateral ports 4 communicatingwith the annular space between the tubing and casing. The lengths of tubing I are shown connected by usual coupling collars 5.

The blow-out preventer includes an annular outer shell which is adapted to seat in the bore of head 3 and an annular inner bushing which is received in the bore of the shell and surrounds the tubing I. The outer shell comprises. upper 25 and lower retaining rings 6 1, rigid with relation to one another and having interposed annular packing 8 of compressiblel and expansible resilient material such as rubber, and presenting an outer peripheral surface of appreciable area 30 adapted for radial engagement with the bore of head 3; and the inner bushing comprises upper and lower annular glands 9 10 adapted for relative longitudinal movement but held against, displacement from the shell, and having interposed 35 annular packing II of compressible and expansible resilientv material such as rubber, the outer periphery of which radially engages the packing 8. The bushing is of relatively small cross-sectional area, so that a relatively small force ex- 40 erted in the direction for longitudinally contracting the glands 9 I0 and thereby longitudinally compressing and radially'expanding the packing I I, is transmitted to the relatively large engagement area of packing 8 for exerting a relatively 45 heavy radial pressure against the head 3 for insuring a. tight pack-off between the blow-out preventer and the head, and at the same time the packing II exerts pressure radially against tubing I for insuring' a tight pack-oil between the 50 blow-out preventer and the tubing.

The outer shell preferably comprises a'plurality of complemental segments adapting the shell for convenient displacement or assembly surrounding the inner bushing; and for this purpose the' shell 55 may be diametrically split throughout its length as shown'at I2 so as to form cooperating halves. 'I'he ring segments 6 1 of each half may be connected by longitudinal pins I3 which may be integral with the ring segments, andthe packing 8 60 may be molded around the pins I3 so that it fills and is retained in the annular space between the ring segments. 'Ihe inner bushing which is received in the shell preferably also comprises a plurality of complemental segments adapting it for convenient displacement or assembly on the well tubing; and for this purpose the glands 9-I il and the packing II may be diametrically split throughout their lengths as shown at Iii', so that the bushing comprises cooperating halves. The proximate ends of glands S-I may be formed with annular lips I5 overlying the ends of packing II for preventing excessive distortion of the packing. In order to longitudinally retain the inner bushing in the outer shell, the proximate ends of glands 9I Il may be provided with flanges I6 adapted to engage shoulders I1 of rings 6-1 for preventing longitudinal displacement of the glands from the bore of the shell while permitting relative longitudinal contraction of the glands responsive to longitudinal pressure, it being noted that a downward force exerted on upper gland 9 will longitudinally compress the packing II against the lower gland I0 which is held against.

downward movement by its flange I6 engaging its cooperating shoulder I1, while upward pressure on lower gland I0 is'adapted to longitudinally cornpress the packing II against the upper gland 9 which is held against upward movement by its flange I6 engaging its cooperating shoulder I1. The packing I I is thus longitudinally compressed and radially expanded by longitudinal force exerted in either of opposite directions, so that the packing II radially engages tubing I and pressure is transmitted from packing II to packing 8 whereby the latter radially engages the bore of head 3.

When the blow-out preventer is in operative position its outer shell is adapted to seat in head 3, and for this purpose the periphery of rings 6-1 may have a shoulder I8 adapted to engage a complemental shoulder I9 in the bore of the head, with the cooperating shoulders I8-I 9 preferably beveled to insure a tight seat and accurately center the blow-out preventer in the head. The periphery of packing 8 may have a slight taper as shown at 20 adapted to engage a complemental tapered bore of the head 3, so as to produce a tight wedging engagement when the packing 8 is operatively expanded.

The split outer shell is held against radial displacement of its segments by its reception in the bore of shell 3 and in turn prevents radial displacement of the segments of the split inner bushing; and before the blow-out preventer has been seated in the head 3 and while it is 4being lowered to operative position it is preferably detachably held against radial displacement of its segments. For this purpose dowel pins 2I may connect the segments of the outer shell, and are preferably threaded'into one of the halves of ring 6 as shown at 22, and are releasably held in bores 23 in the other half of ring 6. The releasable engagement may comprise latch pins 24 which are slidable in longitudinal bores 25 formed in ring 6, with springs 26 positioned between the latch pins and suitable bushings 21 which are threaded into bores 25. The springs yieldably project the latch pins for locking engagement with dowel pins 2I; and

the latch pins are adapted to be rotated so that tapering ribs 28 which are formed on their heads 29 are moved out of engagement with cooperating tapering grooves which are formed in the ends of the bushings 21, thereby causing the heads of the latch pins to ride upwardly relatively to the bushings and thus retracting the latch pins 24% so that they disengage the dowel pins 2I.

Means are provided for releasably locking the blow-out preventer against longitudinal displacement when in operative position, and the locking means is so disposed as to clear the outer periphery of head 3 in order that a bonnet or additional length of casing may be mounted on the head when so desired. As an instance of this arrangement the bore of head 3 and the outer periphery of retaining ring 6 have complementa] annular grooves 3I-32 adapted for transverse alinernent when the blow out preventer is seated in the head, and a resilient split ring 33 is received in groove 3I .and is of a normal diameter whereby its inner periphery extends into the groove 32 as shown at Fig. 1, thereby locking the blow-out preventer against longitudinal displacement from head 3. When lowering the blow-out preventer into the head 3, the inner periphery of the ring 33 projects into the bore of the head and, is thus engaged by the beveled shoulder I8 of retaining ring 1, whereby the resilient locking ring is radially expanded and forced back into groove 3| to permit lowering of the blow-out preventer to its operative position with groove 32 transversely alining with groove 3|; so that through its inherent resiliency the locking ring may then contract to its normal diameter seating partly in the groove 32. The blow out preventer is thus securely locked in place, with its locking means completely enclosed for protection against accidental distortion or injury during handling the device; and the outer periphery of head 3 is clear of obstructions and may thus be adapted for detachable mounting of a bonnet or the like (not shown) as for example by threading the exterior of head 3 as shown at 34.

The locking means is adapted for ready release by radially expanding and holding the resilient ring 33 in its inoperative position retracted entirely within the groove 3|; and the releasing means is arranged so that it does not forma protuberance or projection at the outer periphery of head 3 where it would be liable to be struck and brokenoff or injured. For this purpose a plurality of inclined bores 35 may extend downwardly through ring 6 and open into the groove 32, and keys 36, the lower ends of which are cut away at one side as shown at 31, are adapted for insertion in bores 35 when the blow-out preventer is to be released and withdrawn with the cut away lower ends of the keys clearing the normally contracted locking ring 33. By then rotating the keys 36 as shown at Fig. 4, the sides of their lower ends which are not cut away are moved into engagement with and exert radial pressure against ring 33 for expanding the same and holding it in its inoperative position contracted entirely within groove 3|, whereupon the blow-out preventer may be withdrawn from head 3.

The packing engagement which is made by the blow-out preventer may be tightened by the weight of tubing I, and means are preferably also provided for manually tightening the packing engagement, the tightening action in either case being by relatively longitudinally contracting glands 9-III so as to longitudinally compress packing II and thus radially expand the packing elements 8-II into tight engagement with both the tubing I and the b'ore of head 3. In order to operatively expand the packing by the Weight of the tubing string, the tubing is adapted to be lowered relative to the blow-out preventer until a collar 5 of the tubing string rests upon 75 shown at Fig. 2,

upper gland 9, thereby transmitting the weight of the tubing string to the upper gland for forcing the latterv downwardly relativey to the anchored lower gland I0.

'I'he means for manually tightening the packing` engagement comprises adjusting means between the outer shell and the inner bushing. As an instance of such adjusting means longitudinal bores 40 may be formed in the proximate peripheral surfaces of gland 9 and ring 6, with that part of each bore which extends intothe inner peripheral surface of ring 6 counterbored at the underside of said ring so as to i'orm an abutment shoulder 4|; and bolts 42 are received in the bores 40 with the heads 43 of the bolts received in the counterbores and longitudinally abutting the shoulders 4| at one side of the heads, and having the opposite sides of the heads cut away as shown at 44 so that the gland 9 is free for downward movement relative to the bolts which are held against rotation by their cut away heads abutting the peripheral surface of gland 9 as Nuts 45 are threaded onto the upper ends of the bolts so as to engage the upper end surface of gland 9, and the under side of each nut preferably has an annular rib 46, V- shapedin cross section, and adapted to seat in a complemental groove in the end surface of gland 9 for maintaining alinement of the parts while the nuts are being tightened. It will thus be seen that by screwing -down the nuts 45 the gland 9 is forced downwardly relative to the outer shell, and the gland 9 is thus longitudinally contracted relative .to the anchored lower gland I0 so as to radially expand the packing 8l i.

The invention as thus. described provides for readily assembling and locking the blow-out preventer in operative position and as readily withdrawing and removing the blow-out preventer, with the locking means completely thev device is in operative position, and a tight pack-olf assured by a, relatively small force exerted longitudinally against the inner bushing oi the device.

I claim:

1. A blow-out preventer outer and inner packing, each consisting of expansible and compressible material, means for longitudinally compressing and thereby radially expanding the inner packing, the outer packing being in transverse alinement with the inner packing whereby radial expansion of the inner packing radially expands the outer packing, the outer packing comprising a plurality of comple.- mental segments, and releasable connecting means lfor said complemental segments.-

2. A blow-out preventer comprising an outer shell including end retaining means, and `intery posed packing, and an inner bushing including end glands and interposed packing, each of the packings consisting of expansible and compressible material, the glands'being adapted for relative longitudinal contraction for longitudinally compressing and thereby radially expanding their interposed packing, and the packing of the outer shell being in transverse alinement with the packing of the-inner bushing whereby radial expansion of the packing of the bushing radially expands the packing of the shell.

3. A blow-out preventer comprising an outerl shell including end retaining means and interposed packing, the end retaining means lbeing longitudinally xed relative to one another, and an inner bushing including end glands and interposed packing, each of the packings consisting enclosed whenshell being in transverse comprising radiallyI Y s sible material, the glands being held against 1ongitudinal displacement from the outer shell and, being adapted for relativeA longitudinal contraction for longitudinally compressing and thereby radially expanding their interposed packing, and the packing of the outer shell being in transverse alinement with the packing of the inner bushing whereby radial expansion of the packing of the bushing radially expands the packing of the shell. 5. A blow-out preventer comprising an outer shell including end retaining means and interposed packing, the end retaining means being longitudinally fixed relative to one another, the end retaining means and the interposed packing comprising avplurality' of complemental segments, releasable connecting means for the complemental segments of one of the end retaining means, and an inner bushing including end glands and interposed packing, each of the packings consisting of expansible and compressible material, the glands being adapted for relative longitudinal contraction ior longitudinally compressing and thereby radially expanding their interposed packing, and the packing of the outer alinement with the packing of the inner bushing whereby radial expansion of the packing of the bushing radially ex pands the packing of the shell.

6. A blow out preventer comprising an outer shell including end retaining means and interposed packing, an inner bushing including end glands and interposed packing, longitudinal bolts between one of the end retaining means and the proximate end gland, the heads of the bolts 1ongitudinally abutting the inner end of the retaining means and clearing the proximate gland, and nuts on the outer ends of the bolts engaging the outer end of the gland for longitudinally adjusting the gland relative to the outer shell so as to longitudinally compress and thereby radially expand the packing of the inner bushing, the packing of the outer shell being in transverse alinement with the packing of the inner bushing whereby radial expansion of the packing of the bushing radially expands the packing'of the shell.

7. In combination, a head for well casing, a

- blow out preventer adapted for reception in the for relative longitudinal against relative longitudinal displacement, and l means insertable through the end of said intertting elements for engaging and radially retracting the locking means completely within the head so as to clear the blow-out preventer and thus release the locking means.

8. In combination, a head for well casing, a

blow out preventer adapted for reception in the head so that the head and blow-out preventer constitute intertting elements, a locking means carried by the head and adapted for normal radial contraction so as to engage the blow-out preventer for securing the interfitting elements against relative longitudinal displacement, the locking means being adapted for release by radial expansion and retraction completely within the head so as to clear the blow-out preventer, and means insertable through the end of the intertting elements for engaging and releasing the locking means.

9. In combination, a head for well casing, a

blow out preventer adapted for reception in the head so that the head and blow-out preventer constitute intertting elements, a locking means carried by the head and adapted for normal radial contraction so as to engage the blow-out pre-v venter for securing the intertting elements against relative longitudinal displacement, and means insertable through the end of the blow-out preventer for engaging and radially retracting the locking means completely Within the head so as to clear the blow-out preventer and thus release the locking means.

10. In combination, a head for well casing, a blow-out preventer adapted for reception lin the head so that the head and blow-out preventer.

constitute interfitting elements, an annular groove in each of the intertting elements, a split resilient locking ring of normal diameter adapting it to seat partly in each of the grooves for securing the intertting elements against relative longitudinal displacement, and means insertable through one of the interfltting elements and operable to engage the split ring for radially ex. panding and completely retracting it within the groove of the head so as to clear the blow-out preventer for relative longitudinal displacement of :aid elements, the v blow-out preventer having means at its forward end adapted to engage the locking ring upon insertion of the blow-out preventer in the head, so as to radially expand and retract the ring within the groove in the head to permit alinement of the grooves of the intertting elements for locking engagement by the ring.

l1. In combination, a head for well casing, a blow-out preventer adapted for reception in the head so that the head and blow-out preventer constitute interfitting elements, and a releasable locking means, a part of which is adapted to seat in each of the intertting elements for securing said elements against relative longitudinal displacement, the blow-out preventencomprising radially outer and inner packing and means for longitudinally compressing and thereby radially expanding the inner packing, the outer packing being in transverse alinement with the inner packing whereby radial expansion of the inner packing radially expands the outer packing.

12. A blow-out preventer comprising cooperating radially outer and inner packing means, and an operating connection supported entirely by said cooperating packing means and operable to exert longitudinal pressure against one of said cooperating packing means, the cooperating packing means being arranged whereby said longitudinal pressure against one of said packing means is adapted to radiallyexpand the other of said packing means.

13. In combination, a head for Well casing, a blow-out preventer adapted for reception in the head so that the head and blow-out preventer constitute intertting elements, and a releasable lockingmeans, a part of which is adapted to seat in each of the intertting elements for securing said elements against relative longitudinal dis- 5 placement, the blow out preventer comprising cooperating radially outer and inner packing means, and means for exerting longitudinal pressure against one of said cooperating packing means, the cooperating packing means being arlo ranged whereby said longitudinal pressure against one of said packing means is adapted to radially expand the other of said packing means.

14. In combination, a head for well casing, a blow-out preventer adapted for reception in the l5 head so that the head and blow out preventer constitute intertting elements, a releasable locking means for securing said elements against relative longitudinal displacement, the blow-out preventer comprising radially outer and inner packing, each consisting of expansible and compressible material, and means for longitudinally compressing and thereby radially expanding one of said packings, the packings being in transverse V alinement whereby radial expansion of said one of the packings radially expands the other pack- 15. In combination, a head for well casing, a

blow-out preventer adapted for reception in the head so that the head and blow-out preventer constitute intertting elements, a releasable locking means for securing said elements against relative longitudinal displacement, radially outer and inner packing means for the blow-out preventer, and means for exerting longitudinal pressure against one of said cooperating packing means, the cooperating packing means being arranged whereby said longitudinal pressure against Qne of said packing means is adapted to radially expand the other of said packing means.

16. In combination, a head for Well casing, a blow-out preventer adapted for reception in the head so that the head and blow-out preventer constitute intertting elements, an annular groove in each of the intertting elements, a split resilient locking ring of normal diameter adapting it to seat partly in each of the, grooves for securing the intertting elements against relative longitudinal displacement, and means for engaging and distorting the split ring through its inherent resiliency for retraction completely within the groove of one 'of -the intertting elements so as to permit relative longitudinal displacement of the intertting elements, the Vother of said intertting elements having `means for engaging the split ring during telescoping of the intertting elements so as to distort the ring to its retracted position to permit alinement of the grooves for locking engagement by the ring.

1'7. In combination, a head for well casing, a 60 blow-out preventer adapted for reception in the head so that the head and blow-out preventer constitute intertting elements, an annular groove in each of the intertting elements, a split resilient locking ring of normal diameter adapting it to seat partly in each of the grooves for securing the intertting elements against relative longitudinal displacement, and means for engaging and distorting the split ring through its inherent resiliency for retraction completely within the groove of one of the intertting elements so as to permit relative longitudinal'dis- V placement of the intertting elements.

MILLARD S. BLACK. 

